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171.
Abstract

Nottingham in the 1840s was not only a market town serving the needs of the surrounding agricultural communities of the Trent Valley, but it was also becoming an important manufacturing centre due to the expansion of the lace and hosiery trades. The census return of 1841 records that the town had a population of 53 091 and in addition there were another 17 896 persons in the suburbs of Radford and Sneinton. In assessing the progress of photography in Nottingham, it is of relevance to note however, that although its inhabitants lived in an area of increasing industrial development, they were comparatively isolated from the sophisticated and cosmopolitan influences of the capital city, 123 miles distant. The use of contemporary newspaper reports has been found to be of particular value, therefore, in revealing how the daguerreotype was received by the public, through the eye of the local press, in an atmosphere which was not preconditioned by any fashionable trends.  相似文献   
172.
173.
ABSTRACT: Quality changes of cold smoked salmon from 4 different smokehouses in Europe were monitored by a prototype gas-sensor array system, the FishNose. Samples were stored in different packaging (vacuum and Modified Atmosphere Packaging [MAP]) for up to 4 wk under controlled storage conditions at 5 °C and 10 °C. Quality criteria based on sensory attributes (sweet/sour, off, and rancid odor), and total viable counts and lactic acid bacteria counts were established and used for classification of samples based on the responses of the FishNose. The responses of the gas-sensors correlated well with sensory analysis of spoilage odor and microbial counts suggesting that they can detect volatile microbially produced compounds causing spoilage odors in cold-smoked salmon during storage. The system is therefore ideal for fast quality control related to freshness evaluation of smoked salmon products. Partial least squares (PLS) regression models based on samples from single producer showed better performance than a global model based on products from different producers to classify samples of different quality.  相似文献   
174.
Samples of ten winter wheat varieties, grown at four locations on the eastern side of the UK were assessed for alcohol yield. There was a strong negative association between alcohol yield and grain nitrogen content, but this was strongly influenced by differences between the sites, with a range of alcohol yields observed at given nitrogen levels. Inclusion of grain size parameters, thousand grain weight and grain length:width ratio, along with nitrogen, in a multiple regression, enabled more accurate prediction of alcohol yield for most of the varieties, indicating that grain size would be a useful parameter for selecting the best samples within varieties. A small‐scale measurement of hot water extract, along with grain nitrogen content, gave a reasonable prediction of alcohol yield, but the regression equation was not consistent across seasons. Starch content and turbidity (a measure of the ease of starch release) were both shown to be significantly influenced by variety, but not to give significant correlations with alcohol yield over a range of samples. Positive expression of these characters appeared, however, to contribute to improved alcohol yield in certain of the varieties. It was concluded that different genetic mechanisms influence alcohol yield and that improved breeding lines could be developed by combining positive alcohol yield attributes from complementary parents. Copyright © 2007 Society of Chemical Industry  相似文献   
175.

Purpose

To report a case of lens discontinuation in a long term orthokeratology (OK) lens wearer and describe regression in refraction, corneal topography, and corneal thickness over 408 days after lens discontinuation. Furthermore, the outcome of subsequent LASIK treatment is also reported.

Case report

A 41 year old Caucasian female who had been previously wearing OK lenses for 13 years discontinued lens wear in the left eye to consider refractive surgery in that eye. The greatest changes in subjective and objective refractions, corneal topography and thickness occurred during the first 28 days after lens discontinuation. Subjective refraction did not reach baseline values, but corneal topography parameters returned to pre-OK values after 408 days of no lens wear. The patient then received successful refractive surgery treatment in that eye, achieving uncorrected visual acuity of 0.00 LogMAR units, and residual refractive error within ±0.50 D of emmetropia.

Conclusion

The period of lens discontinuation required for long term OK lens wearers before refractive surgery is likely to vary between individuals and the patient described in this case report required a significant period of lens discontinuation of at least one year before being considered suitable for refractive surgery.  相似文献   
176.
The relative contribution of aroma, taste and texture modalities to overall perception, as well as the interactions which can occur between them, were studied during the consumption of natural foods, i.e. apples. Aroma, taste and texture perceptions were masked in that order by employing different masking agents, separately or combined, allowing one or several of these senses to be omitted during various matching tasks. By means of Common Components and Specific Weight Analysis (CCSWA), matching results were compared to those of rating tests performed by a trained panel, without masking agents. Taste was the modality which contributed most to apple discrimination, followed by texture and aroma. While taste did not seem to interact with texture, its perception may have been amplified by odorant information. A perceptual taste-taste interaction may also occur during apple consumption. The use of masking agents could thus become a useful tool to better understand the perception of several sensations of real natural foods whose formulation cannot be modulated.  相似文献   
177.
Commercial applications of microalgae   总被引:11,自引:0,他引:11  
The first use of microalgae by humans dates back 2000 years to the Chinese, who used Nostoc to survive during famine. However, microalgal biotechnology only really began to develop in the middle of the last century. Nowadays, there are numerous commercial applications of microalgae. For example, (i) microalgae can be used to enhance the nutritional value of food and animal feed owing to their chemical composition, (ii) they play a crucial role in aquaculture and (iii) they can be incorporated into cosmetics. Moreover, they are cultivated as a source of highly valuable molecules. For example, polyunsaturated fatty acid oils are added to infant formulas and nutritional supplements and pigments are important as natural dyes. Stable isotope biochemicals help in structural determination and metabolic studies. Future research should focus on the improvement of production systems and the genetic modification of strains. Microalgal products would in that way become even more diversified and economically competitive.  相似文献   
178.
A high level of antioxidant activity of lipophilic fractions obtained from commercially grown native Australian fruits, as evaluated in the oxygen radical absorbance capacity assay for lipophilic antioxidants (ORAC-L), was identified for the first time. The level of contribution of lipophilic fractions varied from 5.8% (quandong) to 30.7% (riberry) of the total oxygen radical scavenging capacity (ORAC-T). Vitamin E components - ??-tocopherol, ??-tocopherol and ??-tocopherol and lutein - were identified as the main sources of this activity. Among the evaluated sources, Kakadu plum emerges as a fruit with unique nutritional qualities: it exhibited a superior ORAC-T value (430.0 ??M trolox eq/g fresh weight, TEq/g FW) with 26.7% contribution of the lipophilic fraction. The major compounds of Kakadu plum's lipophilic fraction were ??-tocopherol (1.022 ± 0.1 mg/100 g, FW), lutein (0.26 ± 0.01 mg/100 g FW) and chlorophyll a and b (2.72 ± 0.1 and 0.54 ± 0.1 mg/100 g FW, respectively). With regards to mineral content, the levels of major minerals, such as potassium, phosphorus, calcium, magnesium, and trace elements such as iron, zinc, manganese, selenium and copper as well as cobalt, nickel, aluminium and led in native Australian fruits are similar to the levels of these elements in a range of vegetables and frutis produced and consumed elsewhere.  相似文献   
179.
Organophosphorus nerve agents (OPNAs) are highly toxic compounds inhibiting cholinergic enzymes in the central and autonomic nervous systems and neuromuscular junctions, causing severe intoxications in humans. Medical countermeasures and efficient decontamination solutions are needed to counteract the toxicity of a wide spectrum of harmful OPNAs including G, V and Novichok agents. Here, we describe the use of engineered OPNA-degrading enzymes for the degradation of various toxic agents including insecticides, a series of OPNA surrogates, as well as real chemical warfare agents (cyclosarin, sarin, soman, tabun, VX, A230, A232, A234). We demonstrate that only two enzymes can degrade most of these molecules at high concentrations (25 mM) in less than 5 min. Using surface assays adapted from NATO AEP-65 guidelines, we further show that enzyme-based solutions can decontaminate 97.6% and 99.4% of 10 g∙m2 of soman- and VX-contaminated surfaces, respectively. Finally, we demonstrate that these enzymes can degrade ethyl-paraoxon down to sub-inhibitory concentrations of acetylcholinesterase, confirming their efficacy from high to micromolar doses.  相似文献   
180.
Reports an error in "Task planning and energy expended: Exploration of how goals influence performance" by P. Christopher Earley, Pauline Wojnaroski and William Prest (Journal of Applied Psychology, 1987[Feb], Vol 72[1], 107-114). Table 1 on page 109 appeared with reversed labels for the high and low conditions. The corrected Table 1 is provided in the erratum. (The following abstract of the original article appeared in record 1987-17299-001.) Although many studies demonstrate the effectiveness of goal setting in organizations, it is unclear how goals actually influence performance. The present studies examined the effect of assigned goals and task information on performance, energy expended, and task planning or organizing. In Study 1, a 2×2 (Information×Goal) design was used. Subjects were 72 undergraduates working on a business simulation. In Study 2, 129 male and female workers from a service organization and a moving company responded to a survey assessing an individual's goal setting, job training, energy expended during a typical task performance, and task planning undertaken prior to performance. The results of both studies demonstrated that goal setting and task training influenced the dependent variables. In addition to influencing an individual's energy expended (effort and persistence), a specific goal led an individual to plan and organize more than did an individual given a general goal (i.e., "do your best"). The results of both studies suggest that goal setting and task-relevant information influence performance, in part, through their influence on energy expended and planning. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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